We propose to develop and test enzyme inactivators and inhibitors as anticancer agents. The enzyme inactivators are suicide inactivators of K-cat inactivators. They differ from conventional active site directed inactivators in that they are relatively unreactive molecules which are activated at the active site of the enzyme through the catalytic action of the enzyme. Some of the target enzymes are: enzymes which utilize DPN or TPN, tyrosine aminotransferase, S-adenosyl-methionine decarboxylase, ornithine decarboxylase, S-adenosyl-homocysteinase and testosterone reductase. We also propose to develop competitive inhibitors for: methyl-transfer reactions, adenylo-succinate lyase, ornithine decarboxylase, S-adenosyl-methionine synthase and S-adenosyl-methionine decarboxylase. All inhibitors will first be examined with isolated enzymes. If they are active, their mechanism of action will be investigated. They will then be tested in tissue culture against various cell types. If effective, they will be tested in tumor-bearing animals. Anti-tumor activity as well as toxicity, will be evaluated.